Objective: We aimed to evaluate the annual health impacts of particulate matter (PM) less than 10 μm diameter (PM10) and less than 2.5-μm diameter (PM2.5) in 27 cities in Southeast and East Asian countries (Japan, the Philippines, the Republic of Korea, Singapore, and Vietnam) for the year 2009 (n = 50,756,699).Methods: We estimated the number of cases attributable to long-term exposure. We used a scenario that reduced the annual mean values for PM10 and PM2.5 to 20 and 10 μg/m3, respectively.Results: A reduction in long-term exposure to PM10 and PM2.5 would have postponed 8% to 9% of all-cause mortality or about 37,000 deaths. One third of them were associated with cardiopulmonary mortality and one ninth of them were associated with lung cancer mortality.Conclusions: Current air pollution levels in Southeast and East Asian countries have a nonnegligible public health impact.